Method of preparing a flame retarded polyurethane using a flame retarded halogenated polyol

ABSTRACT

A flame retardant, halogenated polyol having the formula ##STR1## wherein R is an aliphatic radical substituted with at least 2 hydroxyl groups, X is a halogen, and X&#39; is a halogen or hydrogen, is used in the reaction mixture for preparing flame retarded polyurethanes.

This application is a division of application Ser. No. 294,699, filedAug. 20, 1981 and now U.S. Pat. No. 4,393,248.

BACKGROUND OF THE INVENTION

The present invention pertains to flame retardant halogenated polyolsand more particularly to flame retardant tri- and tetrahalobutoxypolyols.

Polyurethanes are a widely used group of plastics in industry, havingsuch applications as adhesives, as coatings, as insulators, aselastomers, as cushioning, as packaging materials, as potting resins,and the like. For many of these applications, it is desirable toincorporate a flame retardant into the polyurethane in order to reduceits flammability.

Two commercial, reactive, flame retardants that contain halogens areGAF's 2,3-dibromo-2-butenediol-1,4 and Olin's Thermolin RF-230, achlorinated polyol. U.S. Pat. Nos. 3,919,166 and 4,022,718 describeGAF's product for use as a flame retardant for flexible polyurethanefoam. U.S. Pat. Nos. 3,726,855; 3,741,921; and 3,847,844 describe Olin'sThermolin RF-230 product for use as a flame retardant for rigidpolyurethane foam. None of these patents teaches the present invention.

SUMMARY OF THE INVENTION

The present invention is directed to a flame retardant polyol of theformula ##STR2## wherein a is an integer of 0 or 1, with the provisothat

when a is 0, b is an integer of 1 to 8, R is selected from the groupconsisting of a substituted linear or branched alkyl of 1 to 12 carbonsand a substituted cyclic alkyl of 3 to 12 carbons; X is selected fromthe group consisting of F, Cl, and Br; and X' is selected from the groupconsisting of H, F, Cl, and Br; whereby the substituent is selected fromthe group consisting of at least 2 hydroxyl groups, and when a is 1, bis an integer of 1 to 8, R is selected from the group consisting ofhydrogen, a substituted linear or branched alkyl of 1 to 12 carbons anda substituted cyclic alkyl of 3 to 12 carbons; X is selected from thegroup consisting of F, Cl, and Br; and X' is selected from the groupconsisting of H, F, Cl, and Br; whereby the substituent is selected fromthe group consisting of at least 2 hydroxyl groups.

DETAILED DESCRIPTION OF THE INVENTION

The compositions of this invention are reactive flame retardant polyolsthat react with the isocyanates used in preparing the polyurethanes andthus become permanently bound to the polymer.

The compositions of this invention may be prepared by the addition oftrihalomethanes or tetrahalomethanes to allyl ethers similar to thereactions described by Kharasch, Jensen and Urry in J. Am. Chem. Soc.,69, 1100 (1947). The method of preparation of the composition of thisinvention is as shown by equation (1) below: ##STR3## wherein a, b, X,X' and R are as previously defined.

Another method of preparing some of the compositions of this inventioninvolves the reaction of trihalo or tetrahalobutoxyglycidyl ether withpolyols as shown by equation (2) below: ##STR4## where a, b, X and X'are as defined earlier for Formula I.

The preparation of trichloro and tetrachlorobutoxyglycidyl ethers hasbeen reported by Sadykhzade et al., in Chem. Absts. 85, 32717K (1976).However the reactions of tri- and tetrachlorobutoxyglycidyl ethers withpolyols have not been described.

Representative polyols which may be used to form the compositions ofthis invention according to equation 2 include ethylene glycol,glycerol, trimethylolpropane, trimethylolethane, pentaerythritol,dipentaerythritol, dextrose, fructose, sorbitol, sucrose, etc.

The compositions may also be further reacted with various unsubstitutedor halogen substituted epoxides to increase the molecular weight of theflame retardant and/or increase the halogen content. Epoxides useful forthis purpose include ethylene oxide, propylene oxide,3,3,3-trichloro-1,2-propylene oxide and 4,4,4-trichloro-1,2-butyleneoxide.

The composition of this invention is used as flame retardants forpolyurethane foams in the amount of from 5 to 100 parts of the polyol(php) component by weight to impart a measure of flame retardancy. Thepreferred loadings in rigid polyurethane foam is 25 to 100 php byweight.

Representative compositions of this invention where a of formula I isequal to zero are as follows: Note in the following structures that theletter Q is used as a short-hand way to illustrate the radical ##STR5##wherein X and X' are as previously defined. ##STR6##

Representative compositions of this invention where a of formula I isequal to one are as follows: Note in the following structures that theletter Y is used as a short-hand way to illustrate the radical ##STR7##wherein X and X' are as previously defined. ##STR8##

The preferred compositions of this invention for use as flame retardantsin polyurethane foam are as follows: ##STR9##

The more particularly preferred compositions of this invention are theabove compositions wherein X and X' are Cl.

EXAMPLES

Polyurethane foam described in the following examples is made bydissolving the flame retardant additive in the polyol when used in lessthan 100 php followed by the addition of catalysts, surfactant, water,blowing agent and isocyanate. The mixture is stirred by a high-speedmixer and is poured into a container and allowed to rise. The foam isaged at least overnight, and preferably for seven days, before being cutinto test sections for testing. The flame retardant properties areevaluated using ASTM D-1692-74.

EXAMPLE 1

To a 2-liter three-necked round-bottom glass reaction vessel equippedwith a mechanical stirrer, condenser and addition funnel is added 250.0g (1.4 moles) of trimethylolpropane monoallyl ether. Then 1250 g (6.3moles) of bromotrichloromethane is added and the solution is stirred andrefluxed (105° C.) for 6 hours. The excess bromotrichloromethane isremoved to give 450.0 g (84.5% yield) of crude product.

The infrared spectrum is consistent with the assigned structure. Theviscosity (cps) of this product was determined at 25° C. using aCapillary Viscometer according to the method of ASTM D-445; it was 2,278cps.

An alternate procedure for this preparation involves addingtrimethylolpropane monoallyl ether containing 10% dissolved AIBN[Azobisisobutyronitrile (called Vazo 64) from Dupont] and then adding itto a refluxing solution of bromotrichloromethane.

EXAMPLE 2

To a 12-liter three-necked flask equipped as in Example 1 is added10,000 g (65.2 moles) of carbon tetrachloride which is heated to reflux.Then a solution of 100 g 2-t-butylazo-2-cyanobutane (Luazo 82 fromLucidol) in 1000 g (7.5 moles) of trimethylolpropane monoallyl ether isadded portionwise over a period of 4 hours. After the addition themixture is refluxed for another two hours and an additional 100 g ofLuazo 82 is added. The reaction mixture is then stirred and refluxed foran additional 18 hours. The excess carbon tetrachloride is removed underreduced pressure to give 1750 g (93% yield) of crude product.

The infrared spectrum is consistent with the assigned structure. Theviscosity, determined as in Example 1, was 11,385 cps.

EXAMPLE 3

To a 2-liter three-necked flask equipped as in Example 1 is added 2000 g(13 moles) of carbon tetrachloride which is heated to reflux. Then asolution of 20 g Luazo 82 (Lucidol) in 200 g (1.75 moles) of allylglycidyl ether is added portionwise over a period of 4 hours. After anadditional 2 hours of refluxing another 20 g of Luazo 82 (Lucidol) isadded to the reaction mixture and refluxing continued for an additional18 hours. The excess carbon tetrachloride and allyl glycidyl ether areremoved under reduced pressure to give 394.3 g (84% yield) of crudeproduct.

The infrared spectrum is consistent with the assigned structure.

EXAMPLE 4

To a 2-liter three-necked flask equipped with a mechanical stirrer,condenser, heating mantle with temperature controller, addition funnel,and a nitrogen inlet-outlet are added 128.8 g (1.4 moles) of glyceroland 7.5 g (0.053 mole) of boron trifluoride etherate. The reactionmixture is heated to 90°-100° C. and 750.4 g of the product from Example3 (approximately 2.8 moles) is added over a 35 minute period withoutexternal heating. An exotherm was noted in which the temperature rose to106° C. After the exotherm ceases the reaction mixture is heated at 90°C. for a total reaction time of 31/2 hours.

EXAMPLE 5

To a reaction flask as described in Example 4 are added 13.6 g (0.1mole) of pentaerythritol, and 9.2 g (0.1 mole) ethylene glycol. Then 10drops (0.0028 mole) of boron trifluoride etherate is added and thereaction mixture heated to 100° C. The product of Example 3 (107.2 g,approximately 0.4 mole) was added in about 1 hour. The reaction mixtureis maintained at 100° C. for 6 hours. The temperature is then raised to110°-130° C. for 24 hours.

EXAMPLE 6

To a 5-liter three-necked flask equipped as in Example 1 is added 3200 g(16.0 moles) of bromotrichloromethane which is heated to reflux. Then asolution of 1.0 g of azobis(isobutyronitrile) (Vazo 64 from DuPont) in365.3 g (3.2 moles) of allyl glycidyl ether is added portionwise over a4-hour period. The reaction mixture is stirred and refluxed for a totalof 24 hours and then the excess bromotrichloromethane is removed underreduced pressure to give 1000 g (100% yield) of product.

The infrared spectrum is consistent with the assigned structure.

EXAMPLE 7

To a 250 ml reaction flask equipped as in Example 1 are added 13.7 g(0.1 mole) of allyl glycerol, 1.0 g of azobis(isobutyronitrile) (Vazo 64from DuPont), and 68.5 g (0.35 mole) of bromotrichloromethane. Thereaction mixture is refluxed for 17 hours and then the unreactedstarting material is stripped-off under reduced pressure to give 29.0 g(87% yield) of product.

The infrared spectrum is consistent with the assigned structure.

EXAMPLE 8

To a 5-liter three-necked reaction flask equipped as described inExample 1 is added 3960 g (19.9 moles) of bromotrichloromethane which isheated to reflux. Then a solution of 4.8 g of Vazo 64 in 792.0 g (6.0moles) of allyl glycerol is added over a 4-hour period. The unreactedstarting material is then removed under reduced pressure to give 1823 gof product (87% yield).

The determined infrared spectrum was consistent with the assignedstructure.

The composition of Example 7 or 8 may also be obtained by the acidichydrolysis of the composition of Example 6.

EXAMPLE 9

To a 12-liter three-necked reaction flask equipped as described inExample 1 is added 5994 g (38.9 moles) of carbon tetrachloride which isheated to reflux. Then a solution of 60 g of Luazo 82 in 599.4 g (5.26moles) of allyl glycerol is added dropwise over a period of 5 hours.Then an additional 60 g of Luazo 82 is added and the mixture refluxedfor 17 hours. The unreacted starting materials are removed under reducedpressure to give 1224.2 g (87% yield) of crude product.

The infrared spectrum is consistent with the assigned structure. Theviscosity, determined as in Example 1, was 1,886 cps.

The composition of Example 9 may also be obtained by the acid-catalyzedhydrolyses of the composition of Example 3.

EXAMPLE 10

To a 500 ml reaction flask equipped as described in Example 1 is added100 g (0.84 mole) of chloroform which is heated under reflux. Then asolution of 0.5 g of Vazo 64 dissolved in 10 g (0.09 mole) of allylglycidyl ether is added dropwise over a period of 1 hour. The reactionmixture is refluxed for 24 hours and then concentrated under reducedpressure to give the intermediate product. Acid catalyzed hydrolysis ofthis intermediate gives the desired final product.

EXAMPLE 11

To a 500 ml stirred autoclave are added 160 g (0.43 moles) of thecomposition of Example 1 and 10 drops of boron trifluoride etherate.Then the reaction mixture is heated to 100° C. and 40 g (0.69 moles) ofpropylene oxide is slowly added (1 hr). The reaction mixture ismaintained at 100° C. for 6 hours and then cooled to room temperature togive the product in almost quantitative yield.

EXAMPLES 12-18

A rigid polyurethane foam was prepared using the compositions ofExamples 1, 2, 4, 7 or 8, and 9 and its flame retardant propertiescompared to a foam containing no flame retardant additives. Theseresults are shown in Table 1.

                                      TABLE 1                                     __________________________________________________________________________                        EXAM-                                                                              EXAM-                                                                              EXAM-                                                                              EXAM-                EXAMPLE               COMPOSITION         PLE 12                                                                             PLE 13                                                                             PLE 14                                                                             PLE 15                                                                             EXAMPLE 16                                                                            EXAMPLE                                                                               18                    __________________________________________________________________________    Composition of Example 1                                                                          60.0 --   --   --   --      --      16.0                  Composition of Example 2                                                                          --   96.5 --   --   --      --      --                    Composition of Example 4                                                                          --   --   100.0                                                                              --   --      --      --                    Composition of Examples 7 or 8                                                                    --   --   --   54.2 --      --      --                    Composition of Example 9                                                                          --   --   --   --   100.0   --      --                    Polyol Poly G 71-530 (Olin)                                                                       40.0 3.5  --   45.8 --      --      --                    Polyol Multranol E-9221 (Mobay)                                                                   --   --   --   --   --      100.0   84.0                  Silicone Surfactant DC 193 (Dow                                                                   1.5  1.5  1.5  1.5  1.5     1.8     1.8                   Corning)                                                                      Catalyst Polycat 8 (Abbott)                                                                       1.0  1.3  1.1  1.0  1.3     1.0     1.0                   Catalyst T12 (M & T)                                                                              0.05 --   0.05 0.05 --      0.1     0.1                   Blowing Agent Isotron 11                                                                          30.0 33.0 33.0 30.0 30.0    36.0    33.0                  (Pennwalt)                                                                    Isocyanate Mondur MR (Mobay)                                                                      119.0                                                                              95.0 99.0 128.4                                                                              135.0   125.6   120.1                 NCO/OH Index        1.15 1.15 1.15 1.15 1.15    1.10    1.10                  FLAME RETARDANT PROPERTIES:                                                   ASTM D-1692                                                                   Extent of Burn (inches)*                                                                          0.5  0.6  0.5  0.5  0.5     5.0     3.2                   Rate of Burn (inches/min)                                                                         0.9  1.3  1.0  1.1  0.9     5.0     2.7                   __________________________________________________________________________     *5 inches = Total Sample                                                 

Example 17 shows that without flame retardant additives this rigidpolyurethane foam is totally consumed (5 inches total length of sample)in the ASTM D-1692 test. Example 18 shows that when 16 parts of thecomposition from Example 1 is incorporated into a similar rigidpolyurethane foam formulation, the flame retardancy is markedlyincreased. When 60 parts of this same composition was used the resultingfoam was flame retardant to a much greater extent and burned only 0.5inch (Example 12).

EXAMPLE 19

A rigid polyurethane foam is prepared using the composition of Example 5in place of the composition of Example 4 in Example 14 of Table 1. Theobserved flame retardancy is equivalent to that found for Example 14.

What is claimed:
 1. A flame retarded polyurethane prepared from areaction mixture which comprises an isocyanate, a catalyst, asurfactant, water, a blowing agent, and 5 to 100 parts per hundred partspolyol by weight of a composition having the formula ##STR10## wherein ais an integer of 0 or 1, with the proviso thatwhen a is 0, b is aninteger of 1 to 8, R is selected from the group consisting of asubstituted linear or branched alkyl of 2 to 12 carbons and asubstituted cyclic alkyl of 3 to 12 carbons, X is selected from thegroup consisting of F, Cl, and Br, and X' is selected from the groupconsisting of H, F, Cl, and Br, whereby the substituent is selected fromthe group consisting of at least 1 hydroxyl groups, and when a is 1, bis an integer of 1 to 8, R is selected from the group consisting ofhydrogen, a substituted linear or branched alkyl of 1 to 12 carbons anda substituted cyclic alkyl of 3 to 12 carbons, X is selected from thegroup consisting of F, Cl, and Br, and X' is selected from the groupconsisting of H, F, Cl, and Br, whereby the substituent is selected fromthe group consisting of at least 2 hydroxyl groups.
 2. The compositionof claim 1 wherein a=0, b=1, ##STR11## X'=Br, and X=Cl.
 3. Thecomposition of claim 1 wherein a=0, b=1, ##STR12## and X' and X are Cl.4. The composition of claim 1 wherein a=0, b=1, ##STR13## X'=Br, andX=Cl.
 5. The composition of claim 1 wherein a=0, b=1, ##STR14## and Xand X' are Cl.
 6. The composition of claim 1 wherein a=1, b=2, ##STR15##and X=X'=Cl.
 7. The composition of claim 1 wherein a=0, b=1, X'=H, X=Cland ##STR16##